No One Fits All: From Fixed Prompting to Learned Routing in Multilingual LLMs

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Wu, Wei-Chi, Wei, Sheng-Lun, Huang, Hen-Hsen, Chen, Hsin-Hsi
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866913050537230336
author Wu, Wei-Chi
Wei, Sheng-Lun
Huang, Hen-Hsen
Chen, Hsin-Hsi
author_facet Wu, Wei-Chi
Wei, Sheng-Lun
Huang, Hen-Hsen
Chen, Hsin-Hsi
contents Translation-based prompting is widely used in multilingual LLMs, yet its effectiveness varies across languages and tasks. We evaluate prompting strategies across ten languages of different resource levels and four benchmarks. Our analysis shows that no single strategy is universally optimal. Translation strongly benefits low-resource languages even when translation quality is imperfect, high-resource languages gain little, and prompt-based self-routing underperforms explicit translation. Motivated by these findings, we formulate prompting strategy selection as a learned decision problem and introduce lightweight classifiers that predict whether native or translation-based prompting is optimal for each instance. The classifiers achieve statistically significant improvements over fixed strategies across four benchmarks and generalize to unseen task formats not observed during training. Further analysis reveals that language resource level, rather than translation quality alone, determines when translation is beneficial.
format Preprint
id arxiv_https___arxiv_org_abs_2604_16937
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle No One Fits All: From Fixed Prompting to Learned Routing in Multilingual LLMs
Wu, Wei-Chi
Wei, Sheng-Lun
Huang, Hen-Hsen
Chen, Hsin-Hsi
Computation and Language
Translation-based prompting is widely used in multilingual LLMs, yet its effectiveness varies across languages and tasks. We evaluate prompting strategies across ten languages of different resource levels and four benchmarks. Our analysis shows that no single strategy is universally optimal. Translation strongly benefits low-resource languages even when translation quality is imperfect, high-resource languages gain little, and prompt-based self-routing underperforms explicit translation. Motivated by these findings, we formulate prompting strategy selection as a learned decision problem and introduce lightweight classifiers that predict whether native or translation-based prompting is optimal for each instance. The classifiers achieve statistically significant improvements over fixed strategies across four benchmarks and generalize to unseen task formats not observed during training. Further analysis reveals that language resource level, rather than translation quality alone, determines when translation is beneficial.
title No One Fits All: From Fixed Prompting to Learned Routing in Multilingual LLMs
topic Computation and Language
url https://arxiv.org/abs/2604.16937